Update modules/app.py

modules/app.py

@@ -98,20 +98,20 @@ async def add_audio_to_image(input_data: AudioImageInput):
         raise HTTPException(status_code=500, detail=f"An unexpected error occurred: {str(e)}")
 
 def concatenate_video_audio_clips(clip_names, output_filename):
-    video_streams = []
-    audio_streams = []
+    inputs = []
+    filter_complex = []
 
-    for name in clip_names:
-        input_video = ffmpeg.input(name)
-        video_streams.append(input_video['v'])
-        audio_streams.append(input_video['a'])
+    for i, name in enumerate(clip_names):
+        # For each clip, create separate inputs for video and audio
+        inputs.append(ffmpeg.input(name))
+        # Create filter_complex entries for concatenating without losing sync
+        filter_complex.append(f"[{i}:v][{i}:a]")
 
-    # Concatenate video and audio streams
-    concat_video = ffmpeg.concat(*video_streams, v=1, a=0)
-    concat_audio = ffmpeg.concat(*audio_streams, v=0, a=1)
+    # Generate the filter_complex string for concatenating all clips together
+    filter_complex_string = "".join(f"{x}concat=n={len(clip_names)}:v=1:a=1[v][a];" for x in filter_complex)[:-1]
 
-    # Combine video and audio into a single output
-    ffmpeg.output(concat_video, concat_audio, output_filename, vcodec='libx264', acodec='aac').run()
+    # Execute ffmpeg command with complex filter
+    ffmpeg.output(inputs, output_filename, vcodec='libx264', acodec='aac', **{'filter_complex': filter_complex_string}).run()
 
     return output_filename